View Single Post
  #5   Spotlight this post!  
Unread 16-02-2012, 12:05
billbo911's Avatar
billbo911 billbo911 is offline
I prefer you give a perfect effort.
AKA: That's "Mr. Bill"
FRC #2073 (EagleForce)
Team Role: Mentor
 
Join Date: Mar 2005
Rookie Year: 2005
Location: Elk Grove, Ca.
Posts: 2,355
billbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond repute
Re: Damping the joystick at 1

Quote:
Originally Posted by Ether View Post
Run your joystick commands through a rate-limit filter.

Do the LabVIEW equivalent of this:

Code:
change = joystick - limitedJoystick;
if (change>limit) change = limit;
else (if change<-limit) change = -limit;
limitedJoystick += change;
limit is the amount of change you will allow every iteration

limitedJoystick is the rate-limited joystick value you use to control your motors.

There is a pre-built "PID" function in LabView that does exactly this. Search for "rate limit".
We are using this to keep us from stripping gears on our ball pickup if we reverse directions quickly on it.
Find a control value that works well by experimentation. For our ball pickup, a value of 45 is good. For drive control, you may want a higher number.
__________________
CalGames 2009 Autonomous Champion Award winner
Sacramento 2010 Creativity in Design winner, Sacramento 2010 Quarter finalist
2011 Sacramento Finalist, 2011 Madtown Engineering Inspiration Award.
2012 Sacramento Semi-Finals, 2012 Sacramento Innovation in Control Award, 2012 SVR Judges Award.
2012 CalGames Autonomous Challenge Award winner ($$$).
2014 2X Rockwell Automation: Innovation in Control Award (CVR and SAC). Curie Division Gracious Professionalism Award.
2014 Capital City Classic Winner AND Runner Up. Madtown Throwdown: Runner up.
2015 Innovation in Control Award, Sacramento.
2016 Chezy Champs Finalist, 2016 MTTD Finalist

Last edited by billbo911 : 16-02-2012 at 12:47.
Reply With Quote